package DynamicProgrammingPackage;

public class maxProfit_ {

    // 1. dp[i][0]表示持有股票的最大金额, dp[i][1]表示不持有股票的最大金额
    // 2. 递推公式: dp[i][0] = Math.max(dp[i-1][0],-prices[i]) dp[i][1] = Math.max(dp[i-1][1],dp[i-1][1] + prices[i])
    // 3. 初始化dp[0][0] = -prices[0],dp[0][1] = 0
    // 4. 遍历顺序: 从前向后遍历
    public int maxProfit(int[] prices) {
        int[][] dp = new int[prices.length][2];
        dp[0][0] = -prices[0];
        dp[0][1] = 0;
        for (int i = 1; i < prices.length; i++) {
            dp[i][0] = Math.max(dp[i - 1][0], - prices[i]);
            dp[i][1] = Math.max(dp[i - 1][1], dp[i - 1][1] + prices[i]);
        }
        return Math.max(dp[prices.length - 1][0], dp[prices.length - 1][1]);
    }
}
